docs: def statement_after(self, i):
          """Return the statement after the *i*-th one, or `None`."""
          k = i + 1
          o = len(self.body)
          n = o + len(self.else_body)
          if k > 0:
              if k < o:
                  return self.body.statement(k)
              if k > o and k < n:
                  return self.else_body.statement(k)
          if k < 0:
              if k < o - n and k > -n:
                  return self.body.statement(k)
              if k > o - n:
                  return self.else_body.statement(k)
          return None